From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from smtp4.osuosl.org (smtp4.osuosl.org [IPv6:2605:bc80:3010::137]) by lists.linuxfoundation.org (Postfix) with ESMTP id 103B7C0032 for ; Fri, 29 Sep 2023 13:14:39 +0000 (UTC) Received: from localhost (localhost [127.0.0.1]) by smtp4.osuosl.org (Postfix) with ESMTP id DEEA042DB6 for ; Fri, 29 Sep 2023 13:14:38 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org DEEA042DB6 Authentication-Results: smtp4.osuosl.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.a=rsa-sha256 header.s=20230601 header.b=lJ7rTS+s X-Virus-Scanned: amavisd-new at osuosl.org X-Spam-Flag: NO X-Spam-Score: -2.099 X-Spam-Level: X-Spam-Status: No, score=-2.099 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, DKIM_SIGNED=0.1, DKIM_VALID=-0.1, DKIM_VALID_AU=-0.1, DKIM_VALID_EF=-0.1, FREEMAIL_FROM=0.001, RCVD_IN_DNSWL_NONE=-0.0001, SPF_HELO_NONE=0.001, SPF_PASS=-0.001] autolearn=ham autolearn_force=no Received: from smtp4.osuosl.org ([127.0.0.1]) by localhost (smtp4.osuosl.org [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id rEMW42W9NIBy for ; Fri, 29 Sep 2023 13:14:38 +0000 (UTC) Received: from mail-yb1-xb2f.google.com (mail-yb1-xb2f.google.com [IPv6:2607:f8b0:4864:20::b2f]) by smtp4.osuosl.org (Postfix) with ESMTPS id C4A4442DA0 for ; Fri, 29 Sep 2023 13:14:37 +0000 (UTC) DKIM-Filter: OpenDKIM Filter v2.11.0 smtp4.osuosl.org C4A4442DA0 Received: by mail-yb1-xb2f.google.com with SMTP id 3f1490d57ef6-d81b42a3108so15821179276.1 for ; Fri, 29 Sep 2023 06:14:37 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20230601; t=1695993276; x=1696598076; darn=lists.linuxfoundation.org; h=to:subject:message-id:date:from:mime-version:from:to:cc:subject :date:message-id:reply-to; bh=dYaTCv9WeBroPGo5E2DTBy4OcjUSyEXNUSUVzcsP4uI=; b=lJ7rTS+shVZFGJqogyYcihYLZn80La+lm0j58gSJ3LdJdKab1BokJcF8Ze/KtXOdyc 87NdolhKEJV/hMiijx4/i/oux9ftmUdiod2sMxvVS25EUtNECAiOHE1WyjLDOJ/jy/Ca 1EkoZ0h1dPH8Xz+iUKinCBFLYjJvipeFlk6ftgVkdmBCEJD5HJtRW6WH+CpHYJvVfFxv hV8sPg43Le/bnUbQ0ETpoL7hkwfNoGCdIpCEMV3Ei3VDI7vNJOIUHxN/mzbea83rWSAz 6/Up3dFNZAjtma0UVZiTfXCqXN6FbWJkvxJTElrTOie39knC5jrcieCInck/xNKGbMpf Ik3Q== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20230601; t=1695993276; x=1696598076; h=to:subject:message-id:date:from:mime-version:x-gm-message-state :from:to:cc:subject:date:message-id:reply-to; bh=dYaTCv9WeBroPGo5E2DTBy4OcjUSyEXNUSUVzcsP4uI=; b=ZmNgBKMXRv5nKRSnPZU4gVONcbddCgD0hc/M3nvA4/t2xKkv/24vGehDHW8D8JkEYw L0WjVJJU6TnhbYxxeI/km/x5fdKmC5276XyToRGskHYkNbRO2L6YRzCldZr1/17sMkzd vVxuR8e5I8qzfNdzyipmYzc1VrFB3SnjGk+RffT5i7jatp6k3kXz0uzICYk+4N8OEYkZ my1nRSRGcvkGVxUu96FW4UvyjNkUu51K+075p/DqcKvzmD/dgT7RVBUv22LFCzPtTX/E mRVKLD2spP3MQd0hJHLf1chIZek52kvR0OCq+B7TZf79B1NvgTaurSZBKo1Laer7Hs8N axeQ== X-Gm-Message-State: AOJu0Ywm0AaCLjiQMU675g81aIC/PYzthBOUBezf3pgmjnmpdhHxthjn ZFKwZCHdSy0HUnv7Qpe/k8l9s94WTjdqEV0+9X3oWidiYf940g== X-Google-Smtp-Source: AGHT+IEOM9kaMb5uRDTvYaOHVG5WfNiCgI0FZF5DErNVk01c0OWv0Ndf5jGLyjl7bZ7YjU6csXGZH/i6YGdIUD7WzGU= X-Received: by 2002:a25:5f41:0:b0:d88:a049:e902 with SMTP id h1-20020a255f41000000b00d88a049e902mr4161844ybm.53.1695993276300; Fri, 29 Sep 2023 06:14:36 -0700 (PDT) MIME-Version: 1.0 From: =?UTF-8?Q?Johan_Tor=C3=A5s_Halseth?= Date: Fri, 29 Sep 2023 15:14:25 +0200 Message-ID: To: Bitcoin Protocol Discussion Content-Type: text/plain; charset="UTF-8" X-Mailman-Approved-At: Fri, 29 Sep 2023 15:08:59 +0000 Subject: [bitcoin-dev] MATT: [demo] Optimistic execution of arbitrary programs X-BeenThere: bitcoin-dev@lists.linuxfoundation.org X-Mailman-Version: 2.1.15 Precedence: list List-Id: Bitcoin Protocol Discussion List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Fri, 29 Sep 2023 13:14:39 -0000 Hi, all! I've been working on an implementation of the original MATT challenge protocol[0], with a detailed description of how we go from a "high-level arbitrary program" to something that can be verified on-chain in Bitcoin Script. You can find the write-up here, which also includes instructions of how to run the code and inspect the transactions using a local block explorer: https://github.com/halseth/mattlab/blob/main/docs/challenge.md TLDR; Using the proposed opcode OP_CHECKCONTRACTVERIFY and OP_CAT, we show to trace execution of the program `multiply` [1] and challenge this computation in O(n logn) on-chain transactions: func multiply(x int) int { i := 0 while { if i < 8 { x = x + x i = i + 1 } else { break } } return x } Next steps would be to make this a generic framework with tools to automatically compile arbitrary high-level programs down to MATT-compatible Bitcoin Scripts. All feedback appreciated! - Johan [0] https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-November/021182.html [1] https://lists.linuxfoundation.org/pipermail/bitcoin-dev/2022-November/021205.html